Electronics Forum | Thu Dec 13 20:54:23 EST 2001 | davef
There is neither �nominal thickness� nor �is there a set maximum� for via masking. We use some of our vias as test pads. So, as you�d expect, we get rabid when we get mask bleed onto these pads. IPC-6012 - Qualification & Performance For Rigid Pri
Electronics Forum | Sat Aug 18 11:23:10 EDT 2007 | Learn From U
Hi All, Via X-rays, we found solder voids appear on PTH location, especially on Dimm connectors area. We think this should be related to PCB issue as we found solder unable to fill up the PTH hole during bare board testing at wave soldering machi
Electronics Forum | Mon Jan 17 21:01:21 EST 2000 | Dave F
Dennis: On your BGAs: * Never seen voids any place other than the top ... lower density stuff rises. * Our spec on voids says: 1 Voids 1a Voids in soldered balls shall be less than 20% of the diameter of the solder ball. 1b No void shall sho
Electronics Forum | Fri Mar 02 08:52:20 EST 2001 | markkrmp
Are your voids looking like blow holes also? Is this only occurring on the solder joints of the Thru Hole components and Via's? Or does this happen on SMD pads? My experience is that we have seen this but only with some of our older PCB's which are
Electronics Forum | Wed Mar 14 13:16:54 EDT 2007 | Shane
I have a customer that designed a fine pitch BGA into a board, and has put small vias in the middle of each pad on the PCB. Anyone have any ideas on how I can prevent the solder from the BGA from flowing through the vias and causing voids or no cont
Electronics Forum | Sat Mar 27 08:15:02 EST 2004 | davef
Via in pad is a designer's dream and an assembler's nightmare. Search the fine SMTnet Archives for previous discussions to get started. VIP, via-in-pad, or whatever tend to promote voiding within the via and certainly partially starved solder conne
Electronics Forum | Fri Mar 23 09:13:48 EDT 2007 | Peter W
Hello, those plated and solderable via in pads have two critical points: 1. We have discovered that _sometimes_ the plating seems not to be perfect, as extreme voiding is visible in tha bga solder ball 2. The detection of some defects by AXI is limi
Electronics Forum | Fri Nov 23 16:32:05 EST 2007 | davef
There a several things you can do to prevent the solder wicking down the hole with the current design, and that's where you should focus. Cost goes up as you go down the list, but in neither case do you need to respin the board, have solder starvatio
Electronics Forum | Sat Nov 24 15:44:28 EST 2007 | mika
Hi DaveF, I had a short look into the Nr1. IMPACT OF MICROVIA-IN-PAD DESIGN ON VOID FORMATION Most interesting reading, but one thing though, I could not find any information about the oven profile. Just a picture of it. My question is of about the
Electronics Forum | Thu Jun 28 09:57:50 EDT 2012 | mosborne1
blow holes and via holes are almost always caused by moisture and in PTH they could be moisture and improper drilled holes. If you are seeing solder balls next to the parts than I would say you have a reflow profile problem. Are you using any kind of
